Claims
- 1. An optically active tetrahydropyrane derivative represented by the formula (I): ##STR142## wherein Rf represents a trifluoromethyl or pentafluoroethyl group, R.sup.1 represents a straight alkyl group having 4 to 15 carbon atoms, R.sup.2 and R.sup.3 each independently represent a hydrogen or methyl group, R.sup.4 represents a straight or branched alkyl group having 1 to 10 carbon atoms, X.sup.1 represents --O-- or a single bond, X.sup.2 represents --COO--, or a single bond, X.sup.3 represents --COO--, --CH.sub.2 O-- or --O--, X.sup.4 represents --O-- or --OCO--, * represents an asymmetric carbon, A represents ##STR143## B represents ##STR144## and n represents 0 or 1.
- 2. A liquid crystal composition which comprises
- (a) at least one kind of the compound represented by the formula (I) or (I') as claimed in claim 1,
- (b) a compound having a chiral smectic C phase (SmC* phase) other than (a) or a mixture thereof and/or
- (c) a compound having a smectic C phase (SmC phase) other than (a) or a mixture thereof.
- 3. A liquid crystal composition which comprises
- (a) at least two kinds of the optically active tetrahydropyrane derivatives having the same polarity of spontaneous polarization and different helical sense of a cholesteric phase (N* phase) according to claim 1,
- (b) a compound having a chiral smectic C phase (SmC* phase) other than (a) or a mixture thereof and/or
- (c) a compound having a smectic C phase (SmC phase) other than (a) or a mixture thereof.
- 4. A liquid crystal composition which comprises at least two kinds of optically active tetrahydropyrane derivatives according to claim 1.
- 5. A liquid crystal device which comprises the optically active tetrahydropyrane derivative according to claim 1 interposed between a pair of electrode substrates.
- 6. A liquid crystal device which comprises the liquid crystal composition according to any of claims 2 to 4 interposed between a pair of electrode substrates.
Priority Claims (3)
Number |
Date |
Country |
Kind |
3-344202 |
Dec 1991 |
JPX |
|
4-117488 |
May 1992 |
JPX |
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4-201189 |
Jul 1992 |
JPX |
|
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation-in-part application of application, Ser. No. 08/107,717, filed Aug. 24, 1993 now U.S. Pat. No. 5,368,771.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
5296616 |
Namekawa et al. |
May 1994 |
|
5368771 |
Namekawa et al. |
Nov 1994 |
|
Foreign Referenced Citations (1)
Number |
Date |
Country |
62-226974 |
Oct 1987 |
JPX |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
107717 |
Aug 1993 |
|